Comment 5 for bug 1841104

Hi,
I am working with OpenStack Pike and cloud-init 21.1. I am able to successfully pass dynamic vendor data to the config drive of an instance. However, cloud-init 21.1 just reads all the 'x' bytes of the vendor_data2.json but it doesn't execute the contents of the json. Although, static vendor data works perfectly fine and the YAML file in the JSON is executed as expected by cloud-init 21.1

Relevant part from the cloud-init.log looks like this:

```
2021-04-09 10:51:47,104 - util.py[DEBUG]: Reading from /cfgdrive/openstack/2017-02-22/vendor_data2.json (quiet=False)
2021-04-09 10:51:47,114 - util.py[DEBUG]: Read 74 bytes from /cfgdrive/openstack/2017-02-22/vendor_data2.json
2021-04-09 10:52:02,332 - util.py[DEBUG]: Writing to /var/lib/cloud/instances/74eeba86-84b8-4599-856e-88413029ebc8/vendor-data.txt - wb: [600] 0 bytes
2021-04-09 10:52:02,335 - util.py[DEBUG]: Writing to /var/lib/cloud/instances/74eeba86-84b8-4599-856e-88413029ebc8/vendor-data.txt.i - wb: [600] 308 bytes
2021-04-09 10:52:02,336 - util.py[DEBUG]: Writing to /var/lib/cloud/instances/74eeba86-84b8-4599-856e-88413029ebc8/vendor-data2.txt - wb: [600] 0 bytes
2021-04-09 10:52:02,338 - util.py[DEBUG]: Writing to /var/lib/cloud/instances/74eeba86-84b8-4599-856e-88413029ebc8/vendor-data2.txt.i - wb: [600] 308 bytes
.
.
.
2021-04-09 10:52:02,352 - handlers.py[DEBUG]: start: init-network/consume-vendor-data2: reading and applying vendor-data2
2021-04-09 10:52:02,352 - stages.py[DEBUG]: no vendordata2 from datasource
```

It reads the 74 bytes but doesn't write the value (the YAML file) mapped to key "cloud-init" to the file to vendor-data2.txt, because it was not able to find "vendordata2 from datasource".

My vendor_data2.json looks like this:
`{"testing": {"cloud-init": "#cloud-config\npackage_upgrade: True\npackages:\n - htop"}}`

Please let me know, if this issue is due to my JSON or an issue with how cloud-init handles vendor data. Since this pull request (https://github.com/canonical/cloud-init/pull/777) is fairly new, I am assuming not many people had the chance to test dynamic vendor data using cloud-init yet.